CVE-2021-3426 · cross-distro fix matrix

CVE-2021-3426: There's a flaw in Python 3's pydoc. A local or adjacent attacker who discovers or is able to convince another local or adjacent user to start a pydoc server could access the server and use it to disclose sensitive information belonging to the other user that they would not normally be able to access

Affects 8 Linux releases across 9 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-3426 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

pypy3→ fixed in7.3.3+dfsg-4urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y pypy3
```
python3.9→ fixed in3.9.2-1+deb11u2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y python3.9
```

Debian bookworm

Source: Debian Security Tracker

pypy3→ fixed in7.3.3+dfsg-4urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y pypy3
```

Debian trixie

Source: Debian Security Tracker

pypy3→ fixed in7.3.3+dfsg-4urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y pypy3
```

Alpine v3.20

Source: Alpine secdb

python3→ fixed in3.9.4-r0
```
apk update && apk add --upgrade python3
```

Alpine v3.21

Source: Alpine secdb

python3→ fixed in3.9.4-r0
```
apk update && apk add --upgrade python3
```

Alpine edge

Source: Alpine secdb

python3→ fixed in3.9.4-r0
```
apk update && apk add --upgrade python3
```

Alpine v3.18

Source: Alpine secdb

python3→ fixed in3.9.4-r0
```
apk update && apk add --upgrade python3
```

Alpine v3.19

Source: Alpine secdb

python3→ fixed in3.9.4-r0
```
apk update && apk add --upgrade python3
```

Are YOU affected by CVE-2021-3426?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

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